Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (5): 528-538.DOI: 10.17521/cjpe.2020.0139

Special Issue: 青藏高原植物生态学:植物-土壤-微生物

• Research Articles • Previous Articles     Next Articles

Soil enzyme activities and their influencing factors among different alpine grasslands on the Qingzang Plateau

WANG Zi-Wei1,2,3, WAN Song-Ze3, JIANG Hong-Mao1,2, HU Yang1,2, MA Shu-Qin4, CHEN You-Chao5, LU Xu-Yang1,*()   

  1. 1Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
    2University of Chinese Academy of Science, Beijing 100049, China
    3School of Forestry, Jiangxi Agricultural University, Nanchang 330045, China
    4College of Tourism, Henan Normal University, Xinxiang, Henan 453007, China
    5Wuhan Botanical Garden, Chinese Academy of Science, Wuhan 430074, China
  • Received:2020-05-11 Accepted:2020-07-17 Online:2021-05-20 Published:2020-08-10
  • Contact: LU Xu-Yang
  • Supported by:
    the National Natural Science Foundation of China(41671262);the National Natural Science Foundation of China(41877338)

Abstract:

Aims As a key factor of nutrient cycling in ecosystems, soil enzyme activity is an important indicator of soil quality and ecosystem function. However, there have been very few studies on the differences of soil enzyme activities among different types of alpine grassland ecosystems. Thus, the aims of this study were to compare the differences of soil enzyme activities among five different types of alpine grassland and to reveal their influencing environmental factors on the Qingzang Plateau.
Methods Totally, 21 samples of five alpine grassland types, including alpine meadow, alpine steppe, alpine meadow steppe, alpine desert steppe and alpine desert on northern Qingzang Plateau, were selected for field in-situ investigation and sampling. The activities of 14 enzymes involved in the cycling of carbon (C), nitrogen (N) and phosphorus (P) were determined, and the relationships between enzymatic activities and environmental factors in alpine grassland were established.
Important findings The activities of C-acquisition (invertase, cellulase, β-1,4-glucosidse, polyphenol oxidase and peroxidase), P-acquisition (alkaline phosphatase) enzymes and two N-acquisition (arylamidase and nitrite reductase) were significantly different among different alpine grassland types. Moreover, correlations were found among C-acquisition, N-acquisition and P-acquisition enzymes. A significant positive correlation was found between invertase and alkaline phosphatase, and between cellulase and N-acetyl-α-D-glucosaminidase. A significant negative correlation was found between polyphenol oxidase and nitrite reductase, N-acetyl-β-D- glucosaminidase. Soil organic matter (SOM) content, gram-negative bacteria content, ratio of nitrogen to phosphorus, gram-positive bacteria content, bacteria content, actinomycetes content, total nitrogen content and fungi content were the key factors influencing soil enzyme activity among the 19 environmental indicators, and SOM content had the greatest impact (explained 11.9%). The results demonstrated that the activities of C-acquisition, P-acquisition and two N-acquisition (arylamidase and nitrite reductase) enzymes were significantly different among different types of alpine grassland, and soil enzyme activities were mainly controlled by SOM content, microbes and N elements in alpine grassland ecosystems.

Key words: alpine meadow, alpine steppe, soil enzyme activity, soil microbes, environmental factor